Follicular Unit Removal Tool with Pivoting Retention Member and Method of its Use

ABSTRACT

Tools and methods are provided for removing follicular units from a body surface while improving retention of the follicular units in the removal tool. The removal tool is configured to accommodate a retention member. The retention member may comprise pivotally movable elements which retain the follicular unit in the removal tool. The described tools and methods are especially useful for harvesting follicular units from a body surface in a hair transplantation process.

FIELD OF THE INVENTION

This application is a division of co-pending U.S. patent applicationSer. No. 12/752,889, filed Apr. 1, 2010, and entitled FOLLICULAR UNITREMOVAL TOOL WITH PIVOTING RETENTION MEMBER.

FIELD OF THE INVENTION

The present invention relates generally to tools and methods used forthe harvesting of follicular units, in particular, tools and methodsused in conjunction with hair transplantation procedures.

BACKGROUND OF THE INVENTION

Hair transplantation procedures are well-known, and typically involveharvesting donor hair grafts from the “donor areas,” for example, sideand back fringe areas of the patient's scalp, and implanting them in abald area (“recipient area”). Historically, the harvested hair graftswere relatively large (3-5 mm), although more recently the donor graftsmay be single follicular units, which are naturally occurring aggregatesof 1-3 (and much less commonly, 4-5) closely spaced hair follicles (“theFUs”) that are distributed over the surface of thebody. In onewell-known process, a linear portion of the scalp is removed from adonor area by dissection, using a scalpel to cut down into the fattysubcutaneous tissue. The strip is then dissected (under a microscope)into the component follicular units, which are then implanted into arecipient area in respective puncture incisions made by a needle orrazor blade. Forceps are typically used to grasp and place thefollicular unit grafts into the needle puncture locations, althoughother instruments and methods are known for doing so:

For instance, U.S. Pat. No. 7,172,604 (Cole) discloses an instrument forthe extraction of individual follicular units. U.S. Patent Publication20050267506 (Harris) discloses a method and apparatus for the extractionof follicular units by first scoring the outer skin layers with a sharppunch, and then inserting a blunt punch into the incision to separatethe hair transection. Another U.S. Pat. No. 6,585,746 (Gildenberg)discloses a hair transplantation system utilizing a robotic system,including a robotic arm and a hair follicle end effector associated withthe robotic arm that could be used to harvest hair follicles from thedonor area.

Despite certain advances in improving the tools for harvesting offollicular units, there remains a need for a more efficient harvestingtool that increases the yield of usable harvested specimens, improvesretention of the harvested units in the removal tool and the quality ofthe obtained specimens.

SUMMARY OF THE INVENTION

According to one aspect of the disclosure, a follicular unit removaltool is provided. The tool may comprise an elongated body having a lumenand a distal end with a tip configured to penetrate a body surface, thelumen of the elongated body being configured and having a capacity toreceive one or more follicular units. The tool also comprises aretention member configured to be accommodated by the elongated body andto be pivotally movable from a retracted position to a retentionposition, such that in the retention position at least a portion of theretention member projects into the lumen of the elongated body. Further,the tool comprises an actuator configured to cause the retention memberto pivot from the retraction to the retention position and/or from theretention to the retraction position, wherein the elongated body isconfigured to accommodate the retention member without compromising thecapacity of the lumen available to receive the one or more follicularunits. The removal tool may be manually operated, it could be ahand-held device, or it could be configured to be operatively connectedto a robotic arm and it could be operated using a substantiallyautomated process.

In some embodiments, the elongated body is further configured toaccommodate the retention member without substantially increasing a sizeof a portion of the elongated body that enters a body surface when inuse. In some embodiments, the retention member comprises at least twopivotally movable elements, and wherein an axial movement of theactuator causes the at least two pivotally movable elements to pivotfrom the retracted to the retention position and converge. In furtherembodiments, the elongated body may comprise a depression which providesa pivotal axis for the retention member.

The retention member may be configured to define a portion of theelongated body. The retention member may further comprise aprotuberance, and the actuator may cause the protuberance to be urged ina radial direction and the retention member to pivot. In someembodiments, the portion of the retention member that projects into thelumen may comprise gripping features to grip the follicular unit.

According to another aspect, the method for retaining a follicular unitin the follicular unit removal or harvesting tool is provided. Themethod comprises inserting a follicular unit removal tool comprising anelongated body and a retention member into a body surface, such that adistal end of the elongated body penetrates the body surface andreceives a follicular unit in a lumen of the elongated body. The methodfurther comprises pivoting the retention member between a retractedposition and a retention position such that in the retention position atleast a portion of the retention member projects into the lumen of theelongated body, and in the retracted position the retention memberdefines a portion of the lumen thereof. The method may be substantiallyautomated, for example, performed using a robotic system. Alternatively,the method may be performed using a hand-held device for follicular unitremoval.

In some embodiments of the method, pivoting the retention membercomprises moving an actuator over at least a portion of the elongatedbody. In other embodiments, the method also comprises connecting thefollicular unit removal tool to a source of fluid or gas to assistmovement of the follicular unit in the elongated body in a proximaldirection.

In some embodiments of the method, the retention member may comprise aplurality of pivotable elements, and movement of the actuator causes theplurality of pivotable members to move from the retracted position tothe retention position and converge.

Other and further objects and advantages of the invention will becomeapparent from the following detailed description when read in view ofthe accompanying figures.

BRIEF DESCRIPTION OF THE DRAWINGS

Features and advantages of the embodiments described will becomeappreciated as the same become better understood with reference to thespecification, claims, and appended drawings wherein:

FIG. 1 a is a perspective view of an embodiment of a follicular unitremoval tool of the present application, in its retracted position.

FIG. 1 b is a perspective view of the follicular unit removal tool ofFIG. 1 a, in a position to aid in the description of its structure.

FIG. 2 is an example of a perspective view of a follicular unit removaltool incorporated into a system with an actuator.

FIG. 3 is an end view of FIG. 2.

FIG. 4 a is a schematic cross-sectional view of an example of afollicular unit removal tool in its retracted position.

FIG. 4 b is a schematic cross-sectional view of an example of afollicular unit removal tool in its retention position.

FIG. 5 is an example of a perspective view of a follicular unit removaltool and associated system elements incorporating three pivotablemovable elements.

FIG. 6 is a flow diagram of a method of removing a follicular unitaccording to an embodiment of the present application.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

In the following Detailed Description, reference is made to theaccompanying drawings that show by way of illustration some examples ofembodiments in which the invention may be practiced. In this regard,directional terminology, such as “top,” “bottom,” “inner”, “outer”,“distal,” “proximal,” etc., is used with reference to the orientation ofthe Figure(s) being described. Because components or embodimentsdescribed herein can be positioned in a number of differentorientations, the directional terminology is used for purposes ofillustration and is in no way limiting. It is to be understood thatother embodiments may be utilized and structural or logical changes maybe made without departing from the scope of the present application. Thefollowing description, therefore, is not to be taken in a limitingsense, and the scope of the inventions described is defined by theappended claims.

The devices and methods of the current application are useful in manualprocedures and systems, as well as in automated procedures and system.Some of the automated systems described herein may also berobotically-assisted or computer/software/machine-instructioninstruction controlled. The tools of the current application can also beused with the robotically-assisted systems and procedures and they couldbe configured for use with those robotic systems, for example, asdescribed in the commonly-assigned U.S. Patent Publication No.2007/0106306, the disclosure of which is incorporated herein byreference.

The term “tool”, “follicular unit removal tool” or “harvesting cannula”as used herein refers to any number of tools or end effectors that arecapable of removing or harvesting follicular units (“FUs”) from a bodysurface. A body surface can be attached to the body or may be a flap ofskin or body tissue removed from the body. Such tools may have manydifferent forms and configurations. In many embodiments, the toolcomprises a hollow tubular shaft and thus may be labeled, for example, acannula, a needle, or a punch. The distal end of removal tools (forexample, punches, coring devices, cutting and/or trimming devices,needles), is typically configured to cut and extract the tissue (e.g.,hair follicle).

Various embodiments of follicular unit harvesting cannulas (or tools)described herein may be employed in harvesting systems, whether suchsystems are fully-automated (e.g., robotically controlled),semi-automated, or manually controlled, for example, using hand-helddevices. It will be appreciated by those skilled in the art that eachharvesting cannula design may have certain benefits (e.g., superiorretraction and retention of follicular units, less trauma to thesurrounding skin and tissue), or drawbacks (e.g., complex design and/oroperation, higher manufacturing costs, increased trauma), relative tothe other embodiments. Thus, selection of a particular harvestingcannula distal end design will depend on the particular performancecriteria sought to be achieved.

As mentioned above, the present application is particularly useful inhair harvesting, to provide devices and methods for harvesting hairgrafts, e.g., follicular units (FUs). As such, the term follicular units(or FUs) will be used herein simply as an example for purposes ofdescribing some embodiments with the understanding that it representshair grafts, follicles, or follicular unit(s).

According to an aspect of the present application, there is provided afollicular unit removal or harvesting tool, with a retention member.Removal or harvesting tools generally have a tubular elongated body witha cylindrical profile and a hollow lumen therethrough, although thesetools do not have to be tubular and the profile may be other thancylindrical (e.g., curved and not straight, or other than circular insection). Furthermore, although a particularly useful follicular unitremoval tool includes a hollow lumen that extends through the elongatedbody from one end to another, it is also possible that the lumen onlyextends part way along the length of the elongated body. Moreparticularly, suction or vacuum may be used with the follicular unitremoval tools described herein, and suction may be created through alumen that extends the entire length of the elongated body, or in alumen that only extends part of the way along the body. The retentionmembers described herein may be positioned not only at the distalportion of the tool, but also in various locations along the body of thetool, for example, a short distance from the distal end of the tool, ormidway along the body of the tool, depending upon the configuration ofthe tool and its intended purpose. The terms “coupled,” or “attached,”or “connected,” or “mounted” as used herein, may mean directly orindirectly coupled, attached, integrated, or mounted through one or moreintervening components.

A “retention member” as used herein refers to a structure, or amechanism, or a number of structures and/or mechanisms that partially orfully retain a follicular unit in a lumen of various follicular removaltools. The retention member may translate into or across the lumen, orradially constrict the lumen in a circumferential manner, for example,simply closing tightly about a follicular unit, located in the lumen toimprove its retention and removal without damaging it. The retentionmembers described herein may be made of a variety of biocompatiblematerials, such as polypropylene, polyester, polyurethane, Teflon,Nitinol, stainless steel, etc. The configuration of the retentionmembers may be solid, braided, filamentous, etc., and should not beconsidered limited to any one particular embodiment.

FIGS. 1 a and 1 b illustrate an example of a follicular unit removaltool according to an embodiment of the present application, with somefeatures shown in a somewhat exaggerated configuration in order to aidin the description thereof. The tool 100 comprises an elongated body 102which is illustrated as generally tubular with a hollow interior formingthe lumen 104 thereof, and a distal tip having an opening 106, the tipis configured to penetrate a body surface. The elongated body 102 hasboth an internal diameter 108 and an external diameter 110, either ofwhich may comprise in some embodiments predetermined dimensions. Theinternal and external diameters 108 and 110 define a wall 109 of theelongated body 102. The tool 100 may be used to remove or harvest one ora plurality of follicular units, and will be correspondingly sized,having the capacity to receive the follicular unit or units of interest.For example, the follicular unit removal tool 100 may comprise a lumen104 with a diameter of between about 0.5 and 1.5 mm, having the capacityto receive one or more follicular units. Only a distal portion of thetool 100 is shown, the length and proximal termination varying dependenton how and the type of system with which it is to be used. The tool 100may have a length of between about 4 to 25 mm depending on theapplication. As indicated earlier, in this particular configurationillustrated the tool has a generally cylindrical profile but reduces toa smaller profile at the distal end 112 thereof, tapering towards thedistal tip as shown to more easily facilitate penetration of the bodysurface (not shown). The elongated body 102, in the example shown, hastwo additional side openings, only one 114 a which can be clearly seenin FIG. 1 b. The purpose of these openings will be discussed below.

In one aspect of the present application, a tool 100 is provided whichis configured to accommodate a retention member 120, in such a way thatthe capacity of the lumen 104 available to receive the follicular unitis not compromised or sacrificed by the inclusion of the retentionmember 120. In another aspect of the present application, for example,an overall cross-sectional dimensions, or size, or the cross-sectionalprofile of the follicular unit removal tool as it penetrates the bodysurface with the retention member 120, is not substantially differentfrom the corresponding size, dimensions, or profile of the follicularunit removal tool without such a retention member 120.

The retention member 120 in the configurations illustrated in FIGS. 1-4comprises, as an example, two pivotally movable elements 122 a and 122b. FIG. 1 b shows the pivotally movable elements 122 a and 122 b pivotedsuch that the retention member 120 is in a much exaggerated openposition, with the distal ends 124 a and 124 b of the pivotally movableelements 122 a and 122 b shown to be pivoted substantially away from theelongated body 102. However, the distal ends 124 a and 124 b are movablesuch that they are able to pivot through the side openings 114 a and 114b (not shown) of the elongated body 102 and into the lumen 104 of theelongated body 102. The axes 126 a and 126 b about which the distal ends124 a and 124 b pivot, may be disposed in a depression, such as grooves116 a and 116 b of the elongated body 102. The grooves 116 a, 116 b thusproviding fulcrums about which the pivotally movable elements 122 a and122 b are able to pivot. Although in the example shown in FIG. 1 b, thefulcrum structure provided is in the form of grooves or depressions 116a and 116 b disposed in the outwardly facing surfaces of the elongatedbody 102, it will be appreciated that the fulcrums can be provided byother such suitable structures or features. For example, the fulcrum maybe provided by a shaft in a bearing or a hole. Alternatively, one ormore pivotally movable elements may be attached to a flexible member(e.g., spring) to provide a flexure in place of a fulcrum.

The pivotally movable elements 122 a and 122 b are configured such thatwhen in use, in the retracted position, they may form a part of theelongated body 102, filling in for example the side openings 114 a and114 b. In other words, the surfaces of the movable elements 122 a and122 b that face the lumen 104 of the elongated body 102 (see surface 128b shown in FIG. 1 b) may be substantially aligned with and serve todefine portions of the inner surface of the wall 109 of the elongatedbody 102, thus defining a portion of the lumen of the elongated body.Also, in the retracted position, an outer surface of the retentionmember may lay substantially along an outer surface of the elongatedbody 102. For example, the retention member may be configured to be atleast partially disposed in the wall 109 of the elongated body 102.Therefore, in the retracted position, the pivotally movable elements 122a and 122 b are preferably substantially flush with the lumen wall ofthe elongated body 102 (see FIG. 1 a). By configuring the pivotallymovable elements 122 a and 122 b appropriately, the cross-sectionalprofile (or the footprint) made by the elongated body 102 as itpenetrates the body surface, will therefore be substantially the same asthe cross-sectional profile (or the footprint) made by an elongated bodythat does not incorporate such a retention member.

The pivotally movable elements 122 a and 122 b may have at least aportion of their inwardly facing surfaces 128 a and 128 b respectively,adapted to minimize the trauma experienced by the follicular unit. Suchadaptations including, for example, modification to the shape or finish,and/or the application of a coating to the inwardly facing surfaces 128a and 128 b of the pivotally movable elements 122 a and 122 b.Adaptations may include, but are not limited to, some features thatcomprise non-knife-like, blunt or rounded edges, jagged edges, tapers orother such gradual transitions, crown-like shaping, roughened or ridgedfinishes, that are collectively referred to as gripping features. Thesenon-traumatic inwardly facing surfaces may be incorporated into any ofthe embodiments of the retention members.

The pivotably movable members 122 a, 122 b may be caused to pivot usingan actuator 140. In some embodiments, the actuator may movedistally/proximally substantially parallel to the longitudinal axis ofthe elongated body 102, and control movement of the pivotably movablemembers 122 a and 122 b from the retracted to the retention position, inand out of the respective openings 114 a and 114 b. For example, theactuator 140 illustrated in FIG. 2 takes the form of a simple conicalsleeve that is configured to slide or move over, or on the outer surfaceof the elongated body 102, though it will be apparent that any otherform or shape of actuator 140 will suffice. In the retracted position,the actuator 140 is positioned such that its distal end 142 is disposedproximal to the grooves 116 a, 116 b, of the retention members 120, andthe pivotally movable elements 122 a and 122 b are disposedsubstantially flush with the lumen wall of the elongated body 102. Inthe retention position, the actuator 140 may be positioned such that itsdistal end 142 is disposed distally with respect to the grooves 116 a,116 b, of the retention member 120, and the distal ends 124 a and 124 bof the pivotally movable elements 122 a and 122 b are disposed withinthe lumen 104 of the elongated body 102.

The actuator 140 employed to actuate the pivotally movable elements 122a, 122 b of the retention member may comprise a manual handpiece, forexample, that can be finger/thumb actuated to advance the actuator orsleeve 140 in the distal direction to cause the pivotally movableelements 122 a, 122 b of the retention member 120 to pivot, and to causethe distal ends 124 a, 124 b of the pivotally movable elements 122 a,122 b respectively, to enter the lumen 104 to coapt or converge. Areturn spring (not shown) may cause the actuator or sleeve 140 to returnto its original position, and to allow the retention member 120 toreturn to its original retracted position, as previously described.Alternatively, it may be beneficial to incorporate the actuator 140 intoa substantially automated, or semi-automated system. Specifically, itcould be implemented in a robotically-assisted system, such as thosedescribed in the U.S. Publication No. 2007/0106306 already incorporatedby reference herein. In this particular embodiment the removal tool 100may be carried on an automated (e.g., robotic) arm, so that movement ofthe removal tool relative to the body surface may be performed by eithermovement of the robotic arm relative to the body surface, or movement ofthe removal tool relative to the automated arm, or a combination ofeach. Movement of actuator 140 from a more proximal to a more distalaxial location, as necessary to facilitate pivotable movement of theretention member 120 from the retracted to the retention position, maybe controlled by the provision of stops (not shown), or by a processoror a controller, or by a computer program, or another such mechanism forrestricting such axial movement.

FIG. 3 shows the actuator 140 and the pivotable elements 122 a and 122 bin their retracted positions. The actuator 140 is disposed in a moreproximal position, allowing the inner facing surfaces of the distal ends124 a, 124 b of the retention member 120 to lie substantially flush withthe luminal walls of the elongated body 102, thus enabling the lumen 104to be substantially clear.

FIGS. 4 a and 4 b are cross-sectional views of the retention member 120in operation, though it should be noted that these figures do not followconventional standards, as certain areas are not hatched. The deviationfrom convention serves to aid in clarity of the figures. FIG. 4 a shows,as in FIG. 3, the pivotally movable elements 122 a and 122 b in theirretracted positions. Protuberances 130 a and 130 b may be disposed onthe outer surfaces of the pivotably movable elements 122 a and 122 b. Inthe retracted position, these protuberances are in an elevated or raisedposition with respect to the outermost surface of the elongated body102, while the outer walls of the retention member 120 on either side ofthe protuberances 130 a and 130 b lie substantially in-line with, orflush with the outer walls of the elongated body 102. FIG. 4 b shows theactuator 140 having been moved in the distal direction (indicated by thearrow), such that the protuberances 130 a and 130 b (shown in FIG. 4 a)are urged radially inwards towards the longitudinal axis of the lumen104. To aid in this motion, the protuberances may comprise tapered edgessuch that movement of the actuator 140 in the direction indicated causedthe protuberance to slide easily beneath the actuator 140. This movementin the distal direction actuates the pivotally movable elements 122 aand 122 b such that they pivot about the fulcrums 116 a and 116 b, andthe distal facing portions (the portion distal to the fulcrum) of thepivotally movable elements 122 a and 122 b pivot towards each other. Theproximal ends or portions 132 a and 132 b of the pivotally movableelements 122 a and 122 b that lie proximal to the fulcrum 116 a, 116 b,pivot and move radially outwards away from each other. In this retentionposition, the proximal portions or ends 132 a and 132 b of the pivotallymovable elements 122 a and 122 b are shown to protrude slightly from theouter surface of the elongated body 102, but as indicated, can still beconfined by the structure of the conical actuator 140.

In the retention position illustrated in FIG. 4 b, it can be seen thatany follicular unit that was disposed within the lumen 104 of theelongated body 102 would be retained with the inwardly facing surfaces128 a, 128 b of the pivotally movable elements 122 a and 122 b, and itsmovement impeded in the distal end direction,

Contrary to known retention devices, the inclusion of such a retentionmember 120 in a tool 100 in the manner described enables one to maintain(rather than increase) the external cross-sectional profile or footprintof the tool 100 as it penetrates the body surface, and/or maintain theinternal lumen capacity to that of the maximum capacity dictated by theconfiguration of the internal walls of the tool (rather than compromiseto a lesser capacity dictated by the presence of the retention device).Consequently, the inclusion of such a retention member 120 generallydoes not provide additional “bulk” to the external or internalboundaries of the removal tool 100 in operation, and one is not drivento make certain compromises or sacrifices associated to these externalor internal boundaries in order to facilitate the addition of theretention member. As a result, the harvesting or removal tool does notleave a larger wound in the body surface, and also the size of thefollicular unit or units that can be removed does not have to bedecreased.

FIG. 5 shows that number of pivotally movable elements of the retentionmember may be greater than two, in this particular case there are threepivotally movable elements 142 a, 142 b and 142 c. However, as can beseen, movement of the conical actuator 140 is such that all threepivotable movable elements can be substantially simultaneously pivotallymoved from their retracted to their retention position by the axialmovement of the conical actuator 140 in the distal direction.

In another aspect of the present application, the follicular unitremoval tool may comprise two different tubes that are utilized inconcert to accomplish harvesting of the hair graft. This tool assemblymay include, for example, a pair of coaxially disposed cannulas that aremoveable relative to one another. For example, the elongate body 102that accommodates the retention member, as described, may represent theouter cannula with a blunt distal tip. Such blunt distal tip may be usedfor dissection of tissue around the follicular unit. The tool assemblymay also comprise an inner cannula (not shown) having a relatively sharpdistal end, the inner cannula could move axially within the lumen 104 ofthe elongated body 102. The piercing distal end of the inner cannula maybe, for example, thrust through the lumen 104 of the elongated body 102to pierce the body surface. Then the elongated body 102 may be insertedthrough the incision created by the inner cannula and into the cutaneousand subcutaneous tissue using blunt dissection, for example, toencapsulate and separate from the surrounding tissue the follicular unitchosen for harvesting. The retention member 120, that is accommodated bythe elongated body 102, can then be actuated to pivotally move andretain the follicular unit encapsulated within the lumen 104 of theelongated body 102.

FIG. 6 is a flow diagram of an example of a method 150 that may bepracticed using the follicular unit removal tool described above. Theuser or an operating mechanism (in case of the automated, for example,robotic system), in step 152 moves the removal tool 100 to advance thedistal end of the elongated body 102 to penetrate the body surface of apatient with the retention member 120 in its retracted position. Theretention member 120 may be placed or configured in its retractedposition, for example, before the distal end penetrates the bodysurface, or while it is penetrating the body surface. This configurationmay be carried out simultaneously to the penetration step or as aseparate step. To aid in the penetration of the body surface, theremoval tool 100 may be rotated or otherwise manipulated to furtherpenetration of the body surface. Once within the body surface, theremoval tool is inserted so that its distal end is at the desiredinsertion depth. While the follicular unit is encapsulated within thelumen 104 of the follicular unit removal tool 100, the retention memberis pivoted to the retention position in step 154. Pivotal movement ofthe retention member 120 from the retracted to the retention positionmay be caused, for example, by actuating an actuator 140. In someembodiments, as described hereinbefore, this is facilitated by the axialmovement of the actuator in a distal direction, for example, toencounter the protrusions 130 a, 130 b on the pivotally movable elements122 a, 122 b, and move the distal ends of the pivotally movable elements122 a, 122 b inwards towards the center of the lumen 104 to retain thefollicular unit. Once this action has been accomplished, the user (or anoperating mechanism) may then withdraw the removal tool 100 (step 156)to remove the follicular unit from the body surface. This step may onceagain include rotating the removal tool to aid in the severance of thetethered follicular unit from the body surface. Once withdrawn, andremoved from the body surface, the removal tool 100 may be optionallyreconfigured (e.g., by using the actuator again) such that the retentionmember 120 is in the retracted position within the elongated body 102,and that the lumen 104 is substantially clear. By doing this, in step158, the follicular unit can be released from the removal tool andutilized as desired.

In an alternative embodiment, the step 152 of the method discussed abovemay be modified if, for example, two coaxially disposed cannulas thatare moveable relative to one another are used to remove a follicularunit from a body surface. In this embodiment of the method, in step 152the distal end of an inner cannula (not shown) may be advanced throughthe lumen 104 of an elongated body 102 to penetrate the body surface ofa patient. During this time, it may be preferable to have the retentionmember 120 in its retracted position within the elongated body 102, sothat movement of the inner cannula in the distal direction is notunnecessarily impeded. To aid in the penetration of the body surface,the inner cannula may be rotated or otherwise manipulated to furtherpenetration of the body surface. After initial penetration of the bodysurface with the distal end of the inner cannula, the elonagated body102 may be inserted through the incision created by the inner cannula tothe desired insertion depth. The inner cannula may be partially or fullywithdrawn any time before pivotal movement of the retention memberaccommodated by the elongated body 102 in step 154. As described inreference to the previous example of the method, the pivotal movement ofthe retention member may be achieved by actuating an actuator 140. Therest of the method may remain the same as described above.

It will be apparent that the methods described above may be performedmanually, or they may be partially or substantially automated, includingperformed using robotic systems.

It should be appreciated that any patent, publication, or otherdisclosure material, in whole or in part, that is said to beincorporated by reference herein is incorporated herein only to theextent that the incorporated material does not conflict with existingdefinitions, statements, or other disclosure material set forth in thisdisclosure. As such, and to the extent necessary, the disclosure asexplicitly set forth herein supersedes any conflicting materialincorporated herein by reference.

While the invention has been described in its preferred embodiments, itis to be understood that the words which have been used are words ofdescription and not of limitation. Therefore, changes may be made withinthe appended claims without departing from the true scope of theinvention. By way of non-limiting example, it will be appreciated bythose skilled in the art that particular features or characteristicsdescribed in reference to one figure or embodiment may be combined assuitable with features or characteristics described in another figure orembodiment.

1. A method for retaining one or more follicular units in a follicularunit removal tool, comprising: inserting a follicular unit removal toolcomprising an elongated body and a retention member into a body surface,such that a distal end of the elongated body receives one or morefollicular units in a lumen of the elongated body; and pivoting theretention member between a retracted position and a retention position,such that in the retention position at least a portion of the retentionmember projects into the lumen of the elongated body, wherein in theretracted position the retention member defines a portion of the lumenthereof and a size of an outer and an inner cross-sectional profile of aportion of the follicular unit removal tool that comprises the retentionmember is substantially the same as if the retention member was notpresent.
 2. The method of claim 1, wherein in the retracted position theretention member is at least partially disposed in a wall of theelongated body.
 3. The method of claim 1, wherein pivoting the retentionmember comprises pivoting about a pivotal point positioned between thedistal end and the proximal end of the retention member.
 4. The methodof claim 1, wherein pivoting from the retracted to the retentionposition is carried out without substantially increasing a cross-sectionof a portion of the follicular unit removal tool that enters the bodysurface when the tool is in use, and without compromising a capacity ofthe lumen available to receive the one or more follicular units.
 5. Themethod of claim 1, wherein pivoting the retention member comprisesmoving an actuator over at least a portion of the elongated body.
 6. Themethod of claim 5, wherein moving the actuator comprises moving in adistal and/or proximal direction to cause the retention member to pivot.7. The method of claim 5, wherein the retention member comprises aplurality of pivotable elements and movement of the actuator causes theplurality of pivotable members to move from the retracted position tothe retention position and converge.
 8. The method of claim 5, whereinmoving the actuator causes a distal end portion of the retention memberto move in a direction radially towards a center of the elongated body,and a proximal end portion of the retention member to move in anopposite direction.
 9. The method of claim 5, wherein moving theactuator is controlled by one or more stops, manually, by a processor,by a controller, or by a computer program.
 10. The method of claim 1,further comprising gripping the follicular unit with a non-traumaticsurface of the portion of the retention member that projects into thelumen.
 11. The method of claim 1, wherein the step of insertingcomprises causing an operating mechanism of a robotic system to insertthe follicular unit removal tool into the body surface.
 12. The methodof claim 1, further comprising connecting the follicular unit removaltool to a source of fluid or gas, to assist movement of the one or morefollicular units in the elongated body in a proximal direction.
 13. Themethod of claim 1, wherein the method is substantially automated.
 14. Amethod for retaining one or more follicular units in a follicular unitremoval tool, comprising: inserting a follicular unit removal toolcomprising an elongated body and a retention member into a body surface,such that a distal end of the elongated body receives one or morefollicular units in a lumen of the elongated body; and pivoting theretention member between a retracted position in which the retentionmember defines a portion of the lumen thereof and a retention positionin which as a proximal end of the retention member is urged outward in aradial direction, a distal end of the retention member is urged radiallyinward in an opposite direction into the retention position where atleast a portion of the retention member projects into the lumen of theelongated body.
 15. The method of claim 14, further comprising moving anactuator in a distal and/or proximal direction to cause the retentionmember to pivot.
 16. The method of claim 15, wherein the retentionmember comprises a plurality of pivotable elements and moving theactuator causes the plurality of pivotable members to move from theretracted position to the retention position and converge.
 17. Themethod of claim 14, wherein, when pivoted into the retracted position,the retention member is configured without substantially increasing across-section of a portion of the follicular unit removal tool that isinserted into the body surface, and without compromising the capacity ofthe lumen available to receive the one or more follicular units.
 18. Themethod of claim 14, wherein pivoting the retention member between theretracted position and the retention position comprises moving thedistal end of the retention member through a side opening of theelongated body.
 19. The method of claim 14, further comprising grippingthe follicular unit with the portion of the retention member thatprojects into the lumen.
 20. The method of claim 14, further comprisingwithdrawing the removal tool to remove the follicular unit from the bodysurface and reconfiguring the retention member to the retracted positionwithin the elongated body to keep the lumen substantially clear.